iPhone 18 Pro Charging Slowly? Here's Why and How to Fix It

Your iPhone 18 Pro should charge at 25W wirelessly. Most chargers give it 15W or less. If yours is taking forever to fill up overnight, one of these five causes is almost certainly the reason — and most of them are a 30-second fix.

1. Your Charger Isn't Qi2.2 Certified

This is the most common cause. iPhone 18 Pro supports Qi2.2 at 25W, but standard Qi pads top out at 7.5–15W for iPhone. MagSafe reaches 20W. Only a charger specifically certified for Qi2.2 unlocks the full 25W. Fix: Check the charger's box or listing for "Qi2.2 certified" — not just "Qi2" or "MagSafe compatible." Qi2 without the .2 suffix maxes at 15W.

2. The Power Adapter Is Underpowered

A Qi2.2 charger paired with a 12W or 20W adapter throttles to the adapter's ceiling. For iPhone 18 Pro at 25W, you need a 35W or higher USB-C adapter plugged into the charger. Fix: Check what adapter you're using. Apple's 30W USB-C Compact Power Adapter works. A 12W adapter — common in older Apple boxes — will cap the charge speed.

3. Optimized Battery Charging Is Holding It Back

iOS 27 includes Optimized Charging, which deliberately pauses charging at 80% overnight and finishes just before your usual wake-up time. If the phone is at 80% and it's 2am, it may stay there until 6am by design. Fix: This is working as intended. If you need a full charge right now, go to Settings > Battery > Charging and tap Charge Now. If you want to disable it permanently: Settings > Battery > Battery Health & Charging > toggle off Optimized Battery Charging.

4. A Software Bug Is Throttling Charging

iOS bugs occasionally interfere with charging speed detection or charge management. A fresh restart clears most of them. Fix: Power the phone off completely, leave it off for 10 seconds, restart. Then place it on the charger and check the charge speed indicator: Settings > Battery, tap the current battery percentage to see live wattage output.

5. An iOS Update Is Pending

Some iOS updates include charging management patches. A pending update can cause temporarily reduced charge speeds while the system pre-stages the update in the background. Fix: Settings > General > Software Update. If an update is available, install it. Charging behavior usually normalizes within one cycle after the update.

For Guaranteed 25W Every Time

For guaranteed 25W Qi2.2 charging on iPhone 18 Pro, the AK NextG TriCharge Pro delivers full speed every time — Qi2.2 certified, magnetic fast charge puck for Apple Watch, Qi pad for AirPods. $39.99. Also available on Amazon. Use code LAUNCH15 for 15% off.

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AK NextG is not affiliated with, endorsed by, or sponsored by Apple Inc. Apple, iPhone, AirPods, Apple Watch, iOS, and MacBook are trademarks of Apple Inc.